Moderna Inc has withheld supply of about 1.63 million doses in Japan after it was notified of contamination of its COVID-19 vaccine vials with particulate matter, the U.S. vaccine maker said on August 25.
The contamination, the company said, could be due to a manufacturing issue in one of the production lines at its contract manufacturing site in Spain.
The lot with complaints had 565,400 doses and "out of an abundance of caution" Moderna has put on hold the lot and two adjacent ones.
"To date, no safety or efficacy issues have been identified," Moderna said, adding that it would work with its partner Takeda Pharmaceutical as well as the regulators to address the issue.
Takeda said it conducted an emergency examination after particulate matter was found in a lot of vaccine vials at an inoculation site.
The health ministry said on August 26 it decided to withdraw some doses as a precaution after consultation with Takeda but will strive to minimize the impact of the withdrawal on its inoculation plans.
Prime Minister Yoshihide Suga had said on Wednesday about 60% of the public will be fully vaccinated by September end and that the country had enough vaccines to provide booster doses if such a decision is taken.